sha256($pass.$salt) Hash

What is sha256($pass.$salt)?

SHA-256 is a cryptographic hash function derived from the SHA-2 family of algorithms, standardized by NIST in 2002 as part of FIPS 180-2. The format `sha256($pass.$salt)` represents a hashed password where the plaintext password (`$pass`) is concatenated with a unique salt (`$salt`) before hashing, producing a 256-bit (32-byte) hexadecimal digest. This construction originates from password hashing best practices to mitigate precomputation attacks, with the salt acting as a per-user pepper to ensure identical passwords yield distinct hashes. The primary use-case is secure password storage, where the salted hash prevents rainbow table attacks and enforces computational overhead during verification, though it was later superseded by more modern schemes like Argon2 or bcrypt for enhanced resistance to brute-force and GPU optimizations.

While SHA-256 itself is cryptographically secure against collision and preimage attacks under ideal conditions, the `sha256($pass.$salt)` format is vulnerable due to its reliance on a fixed-length salt (often too short) and the absence of iterative hashing or work factors. Modern attackers leverage GPU/ASIC clusters to perform brute-force or dictionary attacks at unprecedented speeds, exploiting the algorithm’s parallelizability. Additionally, weak salts (e.g., predictable or reused) render the scheme susceptible to rainbow table precomputation, while the lack of built-in slowdown mechanisms (unlike bcrypt’s cost parameter) allows attackers to evaluate millions of hashes per second. Collision resistance remains intact, but the format’s simplicity enables efficient cracking via optimized implementations like CUDA-accelerated hashcat or custom FPGA/ASIC designs.

Identifying sha256($pass.$salt) Hashes

Identifying a hash blindly is often difficult because multiple algorithms can output strings of the exact same length. For example, a standard 32-character hexadecimal string could be MD5, NTLM, MD4, or LM. To definitively identify sha256($pass.$salt), security researchers analyze the hash against a strict regular expression (regex) signature (shown above) to find structural matches.

How to Crack sha256($pass.$salt)

If you need to recover the plaintext password for a sha256($pass.$salt) hash during a penetration test or forensics investigation, you must supply the correct module ID to your cracking software. Use the exact commands provided at the top of this page to target the hash successfully.